A New York City building-inspection sweep didn't find "any hazardous structural issues" at 180 work sites that share a connection to the project team at the Pfizer building office-to-residential conversion, where two support columns buckled last month, the city's Department of Buildings said Tuesday.

The sweep targeted projects associated with four firms also tied to construction at the old Pfizer headquarters, including the developer MetroLoft, contractor Northeast Specialist Group, Barone Steel, and Domani, a private building inspector.

Representatives for the companies didn't immediately respond to requests for comment.

The department began conducting the inspections following the structural failure of the Pfizer building, which is being converted into apartments. On July 7, city officials found two failed columns and several sagging floors and ordered the building evacuated. Work there remains halted, and some construction at three other conversion projects in the city was subsequently ordered to temporarily stop.

The department said it found no evidence that the Pfizer building's structural failure was "inherent" to the fact that it was a conversion.

The Pfizer failure and work stoppages have raised concerns about the safety of converting old skyscrapers into apartments, as these projects have become more common in several U.S. cities in recent years.

The city's latest inspection sweep included 24 other office-to-residential conversions. Though none was deemed structurally hazardous, the department issued three construction violations at those conversions, including one partial stop-work order. The order was issued because two workers were observed operating equipment without adequate lighting. The order has since been lifted, the department said.

At the 156 non-conversion projects inspected in the sweep, the department issued 62 violations and 18 stop-work orders for a variety of issues, including work that didn't match drawings and unauthorized work on a Saturday.

The conversion projects in the sweep had a lower rate of violations than the non-conversion projects, the department said.

The department also said more sweeps are planned, while it continues to investigate what went wrong at the Pfizer building.